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Tumor deposits in axillary adipose tissue in patients with breast cancer:Do they matter? 被引量:1
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作者 Muhammed Mubarak Rahma Rashid Shaheera Shakeel 《World Journal of Clinical Cases》 SCIE 2024年第6期1045-1049,共5页
Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary... Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary tumor.By definition,no residual lymph node structure should be identified in these tumor masses.At present,TDs are mainly reported in colorectal cancer,with a few reports in gastric cancer.There are very few reports on breast cancer(BC).For TDs,current dominant theories suggest that these are the result of lymph node metastasis of the tumor with complete destruction of the lymph nodes by the tumor tissue.Even some pathologists classify a TD as two lymph node metastases for calculation.Some pathologists also believe that TDs belong to the category of disseminated metastasis.Therefore,regardless of the origin,TDs are an indicator of poor prognosis.Moreover,for BC,sentinel lymph node biopsy is generally used at present.Whether radical axillary lymph node dissection should be adopted for BC with TDs in axillary lymph nodes is still inconclusive.The present commentary of this clinical issue has certain guiding significance.It is aimed to increase the awareness of the scientific community towards this under-recognized problem in BC pathology. 展开更多
关键词 Breast cancer Tumor deposits Lymph node metastasis STAGING
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Effects of soil crust on the collapsing erosion of colluvial deposits with granite residual soil
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作者 LIU Weiping ZENG Bohan +1 位作者 WANG Tianhuan DUAN Junyi 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2579-2591,共13页
Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion vo... Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion volumes.However,the impacts of soil crust conditions on the erosion of colluvial deposits with granite residual soils have only been studied to a limited extent.To address this issue,this study investigates the impacts of three soil crust conditions(i.e.,without crust,10-minute crust,and 20-minute crust)on gully morphology,rainfall infiltration,and runoff and sediment yield during slope erosion of colluvial deposits with granite residues(classified as Acrisols)in Yudu County,Ganzhou City,Jiangxi Province,China,using simulated rainfall tests and photographic methods.The results showed that as the strength of the soil crust increased,the capacity of moisture infiltration and the width and depth of the gully as well as the sediment concentration and yield ratio decreased;at the same time,the runoff ratio increased.The sediment yield in the without-crust test was found to be 1.24 and 1.43 times higher than that observed in the 10-minute crust and 20-minute crust tests,respectively.These results indicate that soil crusts can effectively prevent slope erosion and moisture infiltration,while providing valuable insights for the management of soil erosion in natural environments. 展开更多
关键词 Granite residual soil Colluvial deposits Slope erosion Soil crust Sediment yield
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Depositional process of hyperpycnal flow deposits:A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin,Northeast China
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作者 De-zhi Yan Ru-kai Zhu +8 位作者 Hao Shou Zhao-hui Xu Wei-hong Liu Si-cheng Zhu Zhi-cheng Lei Jing-ya Zhang Chang Liu Yi Cai Huai-min Xu 《China Geology》 CAS CSCD 2024年第3期505-516,共12页
Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this... Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits. 展开更多
关键词 Hyperpycnal flow Sedimentary characteristics Depositional process Gravity flow deposit Hyperpycnite Red mud pebble Gray mud pebble Oil and gas exploration engineering Luanping Basin
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Volcanism Pacing Slumping Gravity Flow Deposits during the Late Carboniferous in the Southern Margin of the Junggar Basin,China 被引量:1
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作者 LI Shixin ZHANG Tingshan +7 位作者 ZHANG Xi LIANG Zeliang JI Dongsheng Mihai Emilian POPA YONG Jinjie LUO Jinyu ZENG Jianli ZHU Haihua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1422-1450,共29页
Deep-water gravity depositional processes and evolution in arc systems have become topics of intense research focus in recent years.This study discusses the co-evolution of volcanism and deep-water gravity flow deposi... Deep-water gravity depositional processes and evolution in arc systems have become topics of intense research focus in recent years.This study discusses the co-evolution of volcanism and deep-water gravity flow deposits at the southern margin of the Junggar Basin,based on petrology,geochronology and geochemical analyses.The results show that a massive collapse of unstable sediments from the slope was triggered by volcanism,resulting in the formation of slumping gravity flows.The occurrence of volcanic beds in the slump deposits confirm that synchronous volcanism likely affected sediment instability,triggering gravity flows.The Th/Yb,Ta/Yb and Th/Ta elemental ratios,U-Pb ages of detrital zircons and paleocurrent directions indicate that the North Tianshan(NTS)island arc represents the provenance of the Qianxia Formation.Moreover,statistical data on the pyroclastic components in the gravity flow deposits reveal an intensity index of volcanism,indicating that volcanism is strongly related to gravity flow deposits,especially in terms of the type and distribution of the deposits.A model for volcanically-triggered deep-water gravity flow deposits is established,in order to provide a more in-depth understanding of the co-evolution of volcanism and gravity flow deposits within the depositional setting of the late Paleozoic NTS oceanic subduction margin in the Junggar Basin. 展开更多
关键词 VOLCANISM TRIGGER gravity flow deposits island arc Qianxia Formation Junggar Basin
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Risk factors predict microscopic extranodal tumor deposits in advanced stage Ⅲ colon cancer patients 被引量:1
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作者 Yi-Han Jhuang Yu-Ching Chou +3 位作者 Yu-Chun Lin Je-Ming Hu Ta-Wei Pu Chao-Yang Chen 《World Journal of Gastroenterology》 SCIE CAS 2023年第11期1735-1744,共10页
BACKGROUND Colorectal cancer is a frequent cause of cancer-related mortality in patients with lymph node or distant metastases.Pericolonic tumor deposits(TDs)are considered prognostically distinct from lymph node meta... BACKGROUND Colorectal cancer is a frequent cause of cancer-related mortality in patients with lymph node or distant metastases.Pericolonic tumor deposits(TDs)are considered prognostically distinct from lymph node metastases.AIM To investigate risk factors for extranodal TDs in stage III colon cancer.METHODS This was a retrospective cohort study.We selected 155 individuals diagnosed with stage III colon cancer from the database of the Cancer Registry of the Tri-Service General Hospital.The patients were allocated into the groups with/without N1c.Multivariate Cox regression analysis and Kaplan-Meier method were done.The primary outcomes investigate the association between the covariates and extranodal TDs,and prognostic significance of the covariates regarding the survival.RESULTS There were 136 individuals in the non-N1c group and 19 individuals in the N1c group.Patients with lymphovascular invasion(LVI)had a higher risk of TDs.Overall survival rates of patients with and without LVI were 6.64 years and 8.61 years,respectively(P=0.027).The N1c patients without LVI had higher overall survival than those who with LVI(7.73 years vs 4.42 years,P=0.010).CONCLUSION Patients having stage III colon cancer with LVI have a higher probability of having TDs than those with stage III colon cancer without LVI.Stage III colon cancer patients with TDs and LVI could have poor prognosis and outcome. 展开更多
关键词 Colon cancer Tumor deposits Lymphovascular invasion Risk factor
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Incorporation of perigastric tumor deposits into the TNM staging system for primary gastric cancer 被引量:1
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作者 Yang Li Shuo Li +4 位作者 Lu Liu Li-Yu Zhang Di Wu Tian-Yu Xie Xin-Xin Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第9期1605-1615,共11页
BACKGROUND The current prognostic significance of perigastric tumor deposits(TDs)in gastric cancer(GC)remains unclear.AIM To assess the prognostic value of perigastric TDs and put forward a new TNM staging framework i... BACKGROUND The current prognostic significance of perigastric tumor deposits(TDs)in gastric cancer(GC)remains unclear.AIM To assess the prognostic value of perigastric TDs and put forward a new TNM staging framework involving TDs for primary GC.METHODS This study retrospectively analyzed the pathological data of 6672 patients with GC who underwent gastrectomy or surgery for GC with other diseases from January 1,2012 to December 31,2017 at the Chinese PLA General Hospital.According to the presence of perigastric TDs or not,the patients were divided into TD-positive and TD-negative groups by using the method of propensity score matching.The differences between TD-positive and TD-negative patients were analyzed using binary logistic regression modeling.The Kaplan-Meier method was used to plot survival curves.Multivariate Cox regression modeling and the log-rank test were used to analyze the data.RESULTS Perigastric TDs were found to be positive in 339(5.09%)of the 6672 patients with GC,among whom 237 were men(69.91%)and 102 were women(30.09%)(2.32:1).The median age was 59 years(range,27 to 78 years).Univariate and multivariate survival analyses indicated that TD-positive GC patients had a poorer prognosis than TD-negative patients(P<0.05).The 1-,3-,and 5-year overall survival rates of GC patients with TDs were 68.3%,19.6%,and 11.2%,respectively,and these were significantly poorer than those without TDs of the same stages.There was significant variation in survival according to TD locations among the GC patients(P<0.05).A new TNM staging framework for GC was formulated according to TD location.When TDs appear in the gastric body,the original stages T1,T2,and T3 are classified as T4a with the new framework,and the original stages T4a and T4b both are classified as T4b.When TDs appear in the lesser curvature,the previous stages N0,N1,N2,and N3 now both are classified as N3.When TDs appear in the greater curvature or the distant tissue,the patient should be categorized as having M1.With the new GC staging scheme including TDs,the survival curves of patients in the lower grade TNM stage with TDs were closer to those of patients in the higher grade TNM stage without TDs.CONCLUSION TDs are a poor prognostic factor for patients with primary GC.The location of TDs is associated with the prognosis of patients with primary GC.Accordingly,we developed a new TNM staging framework involving TDs that is more appropriate for patients with primary GC. 展开更多
关键词 Tumor deposits Gastric cancer PROGNOSIS STAGE Overall survival
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Failure mechanism of a large-scale composite deposits caused by the water level increases
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作者 ZHANG Xin TU Guo-xiang +3 位作者 LUO Qi-feng TANG Hao ZHANG Yu-lin LI An-run 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1369-1384,共16页
The failure of slope caused by variations in water levels on both banks of reservoirs is common.Reservoir landslides greatly threaten the safety of reservoir area.Taking large-scale composite deposits located on the L... The failure of slope caused by variations in water levels on both banks of reservoirs is common.Reservoir landslides greatly threaten the safety of reservoir area.Taking large-scale composite deposits located on the Lancang River in Southwest China as a study case,the origin of the deposits was analyzed based on the field investigation and a multi-material model was established in the physical model test.Combined with numerical simulation,the failure mechanism of the composite deposits during reservoir water level variations was studied.The results indicate that the deformation of the large-scale composite deposits is a staged sliding mode during the impoundment process.The first slip deformation is greatly affected by the buoyancy weight-reducing effect,and the permeability of soil and variation in the water level are the factors controlling slope deformation initiation.The high water sensitivity and low permeability of fine grained soil play an important role in the re-deformation of deposits slope.During the impoundment process,the deformation trend of the deposit slope is decreasing,and vertical consolidation of soil and increasing hydrostatic pressure on the slope surface are the main reasons for deformation attenuation.It is considered that the probability of large-scale sliding of the deposits during the impoundment period is low.But the damage caused by local bank collapse of the deposit slope still needs attention.The results of this paper will further improve our understanding of the failure mechanism of composite deposits caused by water level increases and provide guidance for the construction of hydropower stations. 展开更多
关键词 Composite deposits Reservoir water level rise Physical model test Finite-differencemethod Failure mechanism
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Development and validation of a nomogram for preoperative prediction of tumor deposits in colorectal cancer
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作者 Hui-Da Zheng Yun-Huang Hu +1 位作者 Kai Ye Jian-Hua Xu 《World Journal of Gastroenterology》 SCIE CAS 2023年第39期5483-5493,共11页
BACKGROUND Based on the clinical data of colorectal cancer(CRC)patients who underwent surgery at our institution,a model for predicting the formation of tumor deposits(TDs)in this patient population was established.AI... BACKGROUND Based on the clinical data of colorectal cancer(CRC)patients who underwent surgery at our institution,a model for predicting the formation of tumor deposits(TDs)in this patient population was established.AIM To establish an effective model for predicting TD formation,thus enabling clinicians to identify CRC patients at high risk for TDs and implement personalized treatment strategies.METHODS CRC patients(n=645)who met the inclusion criteria were randomly divided into training(n=452)and validation(n=193)cohorts using a 7:3 ratio in this retrospective analysis.Least absolute shrinkage and selection operator regression was employed to screen potential risk factors,and multivariable logistic regression analysis was used to identify independent risk factors.Subsequently,a predictive model for TD formation in CRC patients was constructed based on the independent risk factors.The discrimination ability of the model,its consistency with actual results,and its clinical applicability were evaluated using receiveroperating characteristic curves,area under the curve(AUC),calibration curves,and decision curve analysis(DCA).RESULTS Thirty-four(7.5%)patients with TDs were identified in the training cohort based on postoperative pathological specimens.Multivariate logistic regression analysis identified female sex,preoperative intestinal obstruction,left-sided CRC,and lymph node metastasis as independent risk factors for TD formation.The AUCs of the nomogram models constructed using these variables were 0.839 and 0.853 in the training and validation cohorts,respectively.The calibration curve demonstrated good consistency,and the training cohort DCA yielded a threshold probability of 7%-78%.CONCLUSION This study developed and validated a nomogram with good predictive performance for identifying TDs in CRC patients.Our predictive model can assist surgeons in making optimal treatment decisions. 展开更多
关键词 Colorectal cancer Tumor deposits NOMOGRAM
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A Glance on the Mineral Deposits and Stratigraphic Sequential Variations and Structures in Different Sections of Indus Basin (Pakistan): New Titanosaurian Sauropod Dinosaurs from the Latest Maastrichtian Vitakri Formation of Pakistan
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作者 Muhammad Sadiq Malkani 《Open Journal of Geology》 2023年第10期1069-1138,共70页
Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and othe... Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and other many minerals in different regions which need further exploitation and development. The construction of new water dams in different regions are vital (for availability of cheap electricity), because of available barren and fertile lands and wastage of water as flood. Further the installation of more cement industries in different regions of Indus Basin especially in middle Indus (Sulaiman Range where gypsum, clays and limestones can be available via belt) can increase export to receive more foreign exchange and make local cement cheap for the sustainable development of Pakistan. 31 stratigraphic sequential sections at different sections of Indus basins are presented to know the variation and local stratigraphy. Further here three new titanosaur taxa are being described. Saraikimasoom is based on snout;Gspsaurus, (Maojandino), Nicksaurus and Khanazeem are based on cranial, vertebral and appendicular elements;Balochisaurus, Marisaurus, Pakisaurus, and 3 new genera and species Imrankhanhero zilefatmi, Qaikshaheen masoomniazi and Ikqaumishan smqureshi based on vertebral and appendicular elements;and Sulaimanisaurus and Khetranisaurus based on only caudal vertebrae. Although Pakistani Titanosaurians seem to be proliferated found from one horizon of Vitakri Formation just below the K-Pg boundary they have a wide range of diagnostic features and key elements among titanosaurs which can be used for comparison and phylogenetic analyses with broad updated character data set of titanosaurs. 展开更多
关键词 Mineral deposits Stratigraphic Sequences STRUCTURES Multiple Sections Indus Super Basin New Titanosaurs Latest Maastrichtian Vitakri Formation Pakistan
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The conjunction of factors that lead to formation of giant gold provinces and deposits in non-arc settings 被引量:13
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作者 David I.Groves Richard J.Goldfarb M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第3期303-314,共12页
It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical ... It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical approach thus is required to progressively examine controlling parameters at successively decreasing scales in the total mineral system to understand the location of giant gold deposits in non-arc environments.For giant orogenic,intrusion-related gold systems(IRGS) and Carlin-type gold deposits and iron oxide-copper-gold(IOCG) deposits,there are common factors among all of these at the lithospheric to crustal scale.All are sited in giant gold provinces controlled by complex fundamental fault or shear zones that follow craton margins or,in the case of most Phanerozoic orogenic giants,define the primary suture zones between tectonic terranes.Giant provinces of IRGS,IOCG,and Carlin-type deposits require melting of metasomatized lithosphere beneath craton margins with ascent of hybrid lamprophyric to granitic magmas and associated heat flux to generate the giant province.The IRGS and IOCG deposits require direct exsolution of volatile-rich magmatic-hydrothermal fluids,whereas the association of such melts with Carlin-type ores is more indirect and enigmatic.Giant orogenic gold provinces show no direct relationship to such magmatism.forming from metamorphic fluids,but show an indirect relationship to lamprophyres that reflect the mantle connectivity of controlling first-order structures.In contrast to their province scale similarities,the different giant gold deposit styles show contrasting critical controls at the district to deposit scale.For orogenic gold deposits,the giants appear to have formed by conjunction of a greater number of parameters to those that control smaller deposits,with resultant geometrical and lithostratigraphic complexity as a guide to their location.There are few giant IRGS due to their inferior fluid-flux systems relative to orogenic gold deposits,and those few giants are essentially preservational exceptions.Many Carlin-type deposits are giants due to the exceptional conjunction of both structural and lithological parameters that caused reactive and permeable rocks,enriched in syngenetic gold,to be located below an impermeable cap along antiformal "trends".Hydrocarbons probably played an important role in concentrating metal.The supergiant Post-Betze deposit has additional ore zones in strain heterogeneities surrounding the pre-gold Goldstrike stock.All unequivocal IOCG deposits are giant or near-giant deposits in terms of gold-equivalent resources,partly due to economic factors for this relatively poorly understood,low Cu-Au grade deposit type.The supergiant Olympic Dam deposit,the most shallowly formed deposit among the larger IOCGs,probably owes its origin to eruption of volatile-rich hybrid magma at surface,with formation of a large maar and intense and widespread brecciation,alteration and Cu-Au-U deposition in a huge rock volume. 展开更多
关键词 Giant gold deposits Orogenic gold Carlin deposits Iron oxide-copper-gold deposits Intrusion-related gold systems LITHOSPHERE
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Classification and mineralization of global lithium deposits and lithium extraction technologies for exogenetic lithium deposits 被引量:2
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作者 Mian-ping Zheng En-yuan Xing +5 位作者 Xue-fei Zhang Ming-ming Li Dong Che Ling-zhong Bu Jia-huan Han Chuan-yong Ye 《China Geology》 CAS CSCD 2023年第4期547-566,共20页
A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous n... A reasonable classification of deposits holds great significance for identifying prospecting targets and deploying exploration. The world ’s keen demand for lithium resources has expedited the discovery of numerous novel lithium resources. Given the presence of varied classification criteria for lithium resources presently, this study further ascertained and classified the lithium resources according to their occurrence modes, obtaining 10 types and 5 subtypes of lithium deposits(resources) based on endogenetic and exogenetic factors. As indicated by surveys of Cenozoic exogenetic lithium deposits in China and abroad,the formation and distribution of the deposits are primarily determined by plate collision zones, their primary material sources are linked to the anatectic magmas in the deep oceanic crust, and they were formed primarily during the Miocene and Late Paleogene. The researchers ascertained that these deposits,especially those of the salt lake, geothermal, and volcanic deposit types, are formed by unique slightly acidic magmas, tend to migrate and accumulate toward low-lying areas, and display supernormal enrichment. However, the material sources of lithium deposits(resources) of the Neopaleozoic clay subtype and the deep brine type are yet to be further identified. Given the various types and complex origins of lithium deposits(resources), which were formed due to the interactions of multiple spheres, it is recommended that the mineralization of exogenetic lithium deposits(resources) be investigated by integrating tectono-geochemistry, paleoatmospheric circulation, and salinology. So far, industrialized lithium extraction is primarily achieved in lithium deposits of the salt lake, clay, and hard rock types. The lithium extraction employs different processes, with lithium extraction from salt lake-type lithium deposits proving the most energy-saving and cost-effective. 展开更多
关键词 Exogenetic lithium deposit Endogenetic lithium deposit Deposit type Salt lake type Deep brine type Geothermal type Volcanic deposit type Clay type Supernormal supergene enrichment SGSP lithium extraction techology Invention patent Mineral resource exploration engineering
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Petrogenesis and Physicochemical Conditions of Fertile Porphyry in Non-arc Porphyry Mineralization:A Case from Habo Porphyry Cu-Mo Deposits,SW China 被引量:1
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作者 ZHANG Aiping ZHENG Yuanchuan +4 位作者 SHEN Yang Qi Qunjia WANG Zixuan WU Changda WANG Lu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期469-485,共17页
The Habo deposit is a typical porphyry Cu-Mo deposit in the Ailaoshan–Red River metallogenic belt.Ore minerals in the Habo deposit typically occur as veins in the monzonite porphyry.Zircon U-Pb dating suggests that t... The Habo deposit is a typical porphyry Cu-Mo deposit in the Ailaoshan–Red River metallogenic belt.Ore minerals in the Habo deposit typically occur as veins in the monzonite porphyry.Zircon U-Pb dating suggests that the monzonite porphyry formed at 35.07±0.38 Ma.The monzonite porphyry is characterized by high SiO_(2),Al_(2)O_(3),K_(2)O and Na_(2)O contents,with A/CNK ratios ranging from 0.97 to 1.02.All samples exhibit fractionated REE patterns,characterized by high(La/Yb)N ratios(9.4–13.6,average of 11.2).They show adakite-like geochemical features,high Sr concentrations(627–751 ppm,average of 700 ppm),low Y concentrations(15.13–16.86 ppm,average of 15.81 ppm)and high Sr/Y values(39.5–47.4,average of 44.3).These samples have high initial^(87)Sr/^(86)Sr ratios(0.7074–0.7076)and negativeεNd(t)values(-5.1 to-3.7),whereas the zirconεHf(t)values range from-2.2 to+0.4,suggesting that the monzonite porphyry was derived from the partial melting of a thickened juvenile lower crust.The oxygen fugacity,calculated on the basis of the chemical composition of the amphiboles,shows?NNO values ranging from+1.65 to+2.16(average of 1.94)and lg(fO_(2))ranging from-12.72 to-11.99(average of-12.25),indicating that the monzonite porphyry has high oxygen fugacity.Zircons have high Ce^(4+)/Ce^(3+)ratios(29.29–164.24,average of 84.92),with high?FMQ values ranging from+0.50 to+1.51(average of 0.87)and high lg(fO_(2))values ranging from-14.72 to-12.85(average of-14.07),which also indicates that the oxygen fugacity of the magma was high.The dissolved water content of the Habo monzonite porphyry is 9.5–11.5 wt%,according to the geochemical characteristics,zircon-saturation thermometry(692–794°C)and the mineral phases(amphibole,no plagioclase)in the deep magma chamber.Combined with previous studies,we propose that the high oxygen fugacity and high water content of magma played key roles in controlling the formation of the Habo and other Cu-Mo-Au deposits in the Ailaoshan–Red River metallogenic belt. 展开更多
关键词 magmatic oxidation state water content monzonite porphyry Habo porphyry Cu-Mo deposit Ailaoshan-Red River metallogenic belt
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Types,characteristics and geological significance of event deposits of Chang 9 Member of Triassic Yanchang Formation in southwestern Ordos Basin,NW China 被引量:1
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作者 WANG Ziye MAO Zhiguo +4 位作者 YUAN Xuanjun DENG Xiuqin HUI Xiao ZHANG Zhongyi CUI Jingweil 《Petroleum Exploration and Development》 SCIE 2023年第3期588-602,共15页
Through core observation,thin section identification,and logging and testing data analysis,the types and characteristics of event deposits in the ninth member of Yanchang Formation of Triassic(Chang 9 Member)in southw... Through core observation,thin section identification,and logging and testing data analysis,the types and characteristics of event deposits in the ninth member of Yanchang Formation of Triassic(Chang 9 Member)in southwestern Ordos Basin,China,are examined.There are 4 types and 9 subtypes of event deposits,i.e.earthquake,gravity flow,volcanic and anoxic deposits,in the Chang 9 Member in the study area.Based on the analysis of the characteristics and distribution of such events deposits,it is proposed that the event deposits are generally symbiotic or associated,with intrinsic genetic relations and distribution laws.Five kinds of sedimentary microfacies with relatively developed event deposits are identified,and the genetic model of event deposits is discussed.Seismites are mainly developed in the lake transgression stage when the basin expands episodically,and commonly affected by liquefaction flow,gravity action and brittle shear deformation.Gravity flow,mainly distributed in the high water level period,sandwiched in the fine-grained sediments of prodelta or semi-deep lake,or creates banded or lobate slump turbidite fan.It is relatively developed above the seismites strata.The volcanic event deposits are only seen in the lower part of the Chang 9 Member,showing abrupt contact at the top and bottom,which reflects the volcanic activity at the same time.Anoxic deposits are mostly formed in the late stage of lake transgression to the highstand stage.Very thick organic-rich shales are developed in the highstand stage of Chang 9 Member,and the event deposits in the depositional period of these shales are conducive to potential reservoirs. 展开更多
关键词 event deposit SEISMITE gravity flow anoxic event Triassic Yanchang Formation Ordos Basin
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Mineralization of the Liwu large-scale stratiform copper deposits in Sichuan Province, China: Constraints from fluid inclusions
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作者 Hua-yun Yuan Qing Zhou +6 位作者 Yuan-bao Song Wei Zhang Hui-hua Zhang Tong-zhu Li Tao Yin Chang-nan Wang Gao-lin Tang 《China Geology》 CAS CSCD 2023年第2期252-268,共17页
The Liwu stratiform copper deposit is located in the northwestern Jianglang dome,western China.Current studies mainly focus on the genetic type and mineralization of this deposit.Detailed fluid inclusion characteristi... The Liwu stratiform copper deposit is located in the northwestern Jianglang dome,western China.Current studies mainly focus on the genetic type and mineralization of this deposit.Detailed fluid inclusion characteristics of metallogenic period quartz veins were studied to reveal the ore-forming fluid features.Laser Raman analysis indicates that the ore-forming fluids is a H_(2)O-NaCl-CH_(4)(-CO_(2))system.Fluid inclusions microthermometry shows a homogenization temperature of 181-375°C and a salinity of 5.26%-16.99%for the disseminated-banded Cu-Zn mineralization;but a homogenization temperature of 142-343°C and a salinity of 5.41%-21.19%for the massive-veined Cu-Zn mineralization.These features suggest a medium-high temperature and a medium salinity for the ore-forming fluids.H-O isotopic data indicates that the ore-forming fluids were mainly from the metamorphic and magmatic water,plus minor formation water.And sulfur isotopic data indicates that sulfur was mainly derived from the formation and magmatic rocks.Metallogenesis of the disseminated-banded mineralization was mainly correlated with fluid mixing and water-rock reaction;whereas that of the massive-veined mineralization was mainly correlated with fluid boiling.The genetic type of the deposit is a medium-high temperature hydrothermal deposit related to magmatism and controlled by shear zones.This study is beneficial to understand the stratiform copper deposit. 展开更多
关键词 Stratiform copper deposit MINERALIZATION Fluid inclusion H-O isotopes Hydrothermal deposit Dome structure Middle Proterozoic metamorphic rock Mineral exploration engineering Sichuan Province
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Correlations between trace elements in pyrite and gold mineralization of gold deposits on the North China platform
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作者 Jianzhao Yin Ying Sun +4 位作者 Haoyu Yin Hongyun Shi James Sparling Yuhong Chao Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2023年第6期1079-1103,共25页
By studying both the microscopic physical and chemical typomorphic characteristics of typical mineral pyrite samples associated with representative gold deposits on the north-central margin of the North China Platform... By studying both the microscopic physical and chemical typomorphic characteristics of typical mineral pyrite samples associated with representative gold deposits on the north-central margin of the North China Platform,this paper seeks to identify macroscopic metallogenic mechanisms of gold deposits and to reveal the formation mechanism of lattice gold in pyrite.Typomorphic characteristics of pyrite reveal that pyrite grain size has a negative correlation with gold content.Cubic pyrite,as the dominant crystal form,contains more gold than pentagonal dodecahedral pyrite.Both pyrite crystal forms and chemical compositions indicate that the replacement style of gold deposit formed in a low saturability,low sulfur fugacity,and at temperatures either much higher or much lower than its best forming temperature;comparatively,that of the quartz vein style of gold deposit occurred under conditions with the best temperature,rich in sulfur,and with high sulfur fugacity.The Au/Ag ratios of the pyrites show that both the replacement and quartz vein styles of deposits are mesothermal and hypothermal,while the Co/Ni ratios of the pyrites indicate that the quartz vein style is of magmatic-hydrothermal origin.The X-ray diffraction intensity of pyrite rich in gold is lower than that of pyrite poor in gold at the quartz vein style.In general,with an increase in gold content in pyrite,the total sum intensityΣI decreases.The pyroelectricity coefficient has a negative correlation trend with the values of(Co+Ni+Se+Te)-As and(Co+Ni+Se+Te)/As.The pyrite pyroelectricity of the replacement style is N-type,indicating that it formed under low sulfur fugacity,while that of the quartz vein style is a mixture of P-N types,indicating that it formed under high sulfur fugacity.On the pyroelectricity-temperature diagram,pyrite of the replacement style is mainly distributed between 200 and 270°C,while that of the quartz vein style varies between 90–118 and274–386°C,demonstrating a multistage forming process.In contrast to previous researchers'conclusions,the authors confirm the existence of lattice gold in pyrites through the use of an electron paramagnetic resonance(EPR)test.Au in the form of Au~+,entering pyrite as an isomorph and producing electron–hole centers,makes the centers produce spin resonance absorption and results in EPR absorption peak II.The intensity of auriferous pyrite absorption peak II has certain direct positive correlations with pyrite gold content.The#I and#III absorption peaks of pyrites possibly result from the existence of Ni^(2+)and/or Cu^(2+).γ1,γ2,andγ3 are the strongest and most typical absorption peaks of the infrared spectra of the pyrites.Generally,with the increase in gold content in the pyrite samples,γ1,γ2,andγ3 tend to shift to higher wavenumbers,and the gold content in the pyrite samples has a positive correlation with their relative absorbance. 展开更多
关键词 Unit cell parameter PYROELECTRICITY Electron paramagnetic resonance Infrared spectrum PYRITE Gold deposit
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New Progress in the Study of “Pre-war Deposits”
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作者 HUANG Chuanrong 《Cultural and Religious Studies》 2023年第9期420-428,共9页
At present,the academic researches on the issue of“pre-war deposits”in the banking industry mainly focus on the problems of inflation during the war and after the war,the business operation of the banking industry d... At present,the academic researches on the issue of“pre-war deposits”in the banking industry mainly focus on the problems of inflation during the war and after the war,the business operation of the banking industry during the war,the demobilization,reorganization,and currency reform of the banking industry after the war,and so on.The direct related researches are few and focus on the disputes between depositors and banks.Although some archival materials and newspaper materials have been excavated,various kinds of historical materials still need to be further excavated.Research methods need to further strengthen interdisciplinary and integration.Therefore,to deepen the study of“pre-war deposit”,it is necessary to continuously explore and utilize new historical materials,expand research fields,expand research horizons,and pay attention to the use of multi-scientific theories and methods. 展开更多
关键词 pre-war deposit problem interdisciplinary integration expand the research field excavate new historical materials
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A Preliminary Review of Metallogenic Regularity of Molybdenum Deposits in China 被引量:7
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作者 HUANG Fan LIU Xinxing +1 位作者 WANG Denghong WANG Chenghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期972-1001,共30页
Molybdenum is one of the dominant minerals in China because of its rich reserves.In recent years,outstanding breakthroughs have been made in molybdenum prospecting in China,and the distribution of molybdenum deposits ... Molybdenum is one of the dominant minerals in China because of its rich reserves.In recent years,outstanding breakthroughs have been made in molybdenum prospecting in China,and the distribution of molybdenum deposits in China is found to have a "planar pattern".In general,the molybdenum deposits are concentrated in eastern China,including the largest molybdenum reserves of Henan Province.In terms of the scale of molybdenum deposits,the identified resources of the superlarge deposits are the most important,which account for about 53% of the whole country,and those of the large deposits account for about 30%,those of the medium-sized deposits account for about 14%,those of the small-sized deposits,mine spots and mineralization account for about 3%.The molybdenum deposits are mainly classified as porphyry type,skarn type,hydrothermal(vein) type and sedimentary(metamorphic) type in genesis,and the identified resources of these types account for 85.75%,8.83%,2.79%and 2.63% of the total resources respectively.Based on the statistics of precise chronology data of molybdenites Re-Os,Mo-mineralization can be divided into 6 periods in Chinese geological history,which are Precambrian(〉800 Ma),Cambrian-Silurian(540-415 Ma,Caledonian),Devonian-Permian(400-290 Ma,Hecynian),Triassic(260-200 Ma,Indosinian),Jurassic-Cretaceous(195-70 Ma,Yanshanian) and Paleogene-Neogene(65-10 Ma,Himalayan).Mo mineralization during the Yanshanian period is the strongest one,in which about 76.69% of the Chinese total identified resources was formed.The second is the Himalayan period.According to spatial-temporal distribution characteristics of molybdenum deposits,the metallogenic regularity of molybdenum deposits was preliminarily summarized,and 41 level-Ⅲ molybdenum-forming belts,13 level-Ⅱ molybdenum-forming provinces and 4 level-Ⅰ molybdenum-forming domains were ascertained in the mainland of China.There are 39 metallogenic series of and 60 sub-series of molybdenum deposits with molybdenum as the dominant metal and corresponding representative molybdenum deposits proposed.Metallogenic lineages of molybdenum deposits were also established.Spatial-temporal evolution of different types of molybdenum deposits,and the relationship between Mo-mineralization and tectonic evolution have been discussed in this paper.On this basis,the authors think that element Mo is an effective tracer for recording the crustal evolution history of China.At present,there are some problems in the exploration of Mo deposits in China,such as uneven exploration degrees in eastern and western China,shallow exploration depth,low and uneven grade,complex associated components,difficulty of mineral development and utilization,increasing costs of prospecting,and so on.According to successful experience of superficial and deep prospecting and considering also the discussion above,some suggestions are proposed for the prospecting of molybdenum deposits in the future. 展开更多
关键词 molybdenum deposits deposits type molybdenum-forming belt regional metaUogeny tectonic evolution suggestion for prospecting
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A Preliminary Review of Metallogenic Regularity of Tin Deposits in China 被引量:1
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作者 CHEN Zhenghui SHENG Jifu +3 位作者 LIU Lijun WANG Denghong LIANG Ting WANG Chenghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期1021-1035,共15页
China is rich in tin resources,and contains many types of tin deposits.Among the tin deposit types,the cassiterite-sulfide type,skarn type and quartz vein type occupy a large proportion of tin resources and reserves.F... China is rich in tin resources,and contains many types of tin deposits.Among the tin deposit types,the cassiterite-sulfide type,skarn type and quartz vein type occupy a large proportion of tin resources and reserves.From the aspect of exploitation and utilization,the most important types are cassiterite-sulfide type and quartz vein type.The cassiterite-sulfide type tin deposits are mainly located in Northern Guangxi and Eastern Yunnan,skarn type deposits are mainly distributed in the ore-concentration areas of South Hunan in Middle Nanling,and the quartz vein type tin deposits are mainly distributed in South China,such as Western Fujian,Middle Jiangxi,Northern Guangzhou and Southern Hunan.The most important metallogenic epoch for tin deposits is the Mesozoic era.The metallogenic geotectonic background is mainly continental environments after orogeny process,with strong tectonic changes,interlaced deep fracture and frequent magmatism.And the most distinctive feature is the well developed Mesozoic granites,which have a close relationship with tin mineralization.Based on the detailed study of the data from 873 tin deposits in China,this paper summarized the metallogenic regularity of tin deposits,classified 20 important metallogenic series of tin or tin-associated deposits,and inferred that the cassiterite-sulfide type,skarn type,quartz vein type and greisen type are the main prediction types of tin resources.Forty-four tin-mineralization belts were divided,among which,19 belts are the most important.In addition,a series of maps about tin metallogenic belts and tin metallogenic regularity were compiled,aiming to provide theoretical basis for potential estimation and prediction of tin mineral resources. 展开更多
关键词 tin deposits type of tin deposits mineralization epoch tin metallogenic belt metallogenicregularity
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Intrusion-related Gold Deposits in Egypt
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作者 Nagy Shawky BOTROS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第3期1033-1055,共23页
Intrusion-related gold deposits(IRGDs)occur in the Eastern Desert(ED)of Egypt within magmatic districts that are exploited for tungsten and tin mineralization.IRGDs and intrusion-related rare metal deposits(IRRMDs)are... Intrusion-related gold deposits(IRGDs)occur in the Eastern Desert(ED)of Egypt within magmatic districts that are exploited for tungsten and tin mineralization.IRGDs and intrusion-related rare metal deposits(IRRMDs)are almost invariably linked with the late to post collisional Younger Granites(YGs)that have three successive phases(Ⅰ,ⅡandⅢ).At~635–630 Ma,the ED underwent a transition in deformation style from compressional to extensional and a switch from subduction with crustal thickening to delamination with crustal thinning.This transition was concurrent with the emplacement of a short magmatic pulse(~635–630 Ma)that represents a transition between orogenic gold deposits and IRGDs.K-rich calc alkaline granites(phaseⅠandⅡof the YGs)hosting IRGDs like the Hangalia deposit were emplaced during the time span 630–610 Ma.Alkaline magmatism began at 610 Ma,coexisting with the K-rich calc-alkaline magmatism over the 610–590 Ma time span,where the Fawakhir(598±3 Ma)and Um Had(596±2 Ma)granites that host the IRGDs were emplaced.In time,the alkaline magmatism became more alkaline giving rise to phaseⅢof the YGs that hosts IRRMDs.A distinct metallogenic epoch comprising both IRGDs and IRRMDs,was undergoing extreme growth at~600 Ma. 展开更多
关键词 intrusion-related gold deposits intrusion-related rare metal deposits delamination crustal melting metallogenic epoch ~600 Ma Younger Granites
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Classification,Minerogenic Models and Prospecting of Realgar/Orpiment Deposits in China
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作者 XIONG Xianxiao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期618-622,共5页
China's realgar/orpiment deposits may be classified into three types, the stratabound, hot-water sedimentary and hydrothermal, according to their mineralizing processes, geological occurrences, tectonic and geoche... China's realgar/orpiment deposits may be classified into three types, the stratabound, hot-water sedimentary and hydrothermal, according to their mineralizing processes, geological occurrences, tectonic and geochemical features. The three types may be further distinguished into seven subtypes, namely, the Xiaguan, Shuiluo, Jiepaiyu, Songpan, Shixia, Wangzhuang and Ninghshan ones. On this basis three minerogenic models are established, and based on studies of their geochemistry and minerogenic mechanisms the prerequisites for prospecting for these types of deposits are given in the paper. 展开更多
关键词 realgar/orpiment deposits classification of deposits minerogenic model ore prospecting China
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